Spark plugs, high altitude ops and caravan

[Ken Chambers]

There was a recent question about spark plugs. Several years ago I bought a set
of Bosch Platinum WR7BP plugs from Hugh. I
finally installed them in a running Amphicar and they work just fine. Last
weekend I took the car on a 500 mile round trip to the
High Sierras for some camping and boating at a 6500 foot elevation lake just
west of Lake Tahoe. The engine ran very rich at that
altitude as evidenced by hard starting, low power output and a sooty tail pipe.
Nevertheless, Amphi performed absolutely
flawlessly for the entire adventure. It handled very well on the road, too,
after the recent toe-in adjustment. Upon returning to
near sea level, I noticed that the black soot that was present inside the tail
pipe is now gone, replaced by the normal thin
grayish color again. Has anyone had any success changing the high speed
metering orifice in their Solex carb to get a leaner
fuel/air mixture? Does anyone know the correct sizes for altitude ranges? Any
advice to the group would be much appreciated.

I had so much fun on this driving adventure that I've actually been toying with
the idea of driving Amphi from the west coast to
Celina next year. I'd better plan on an extended vacation, not that Amphi is
all that slow but because of all those lakes in all
those states along the way. It would be fun to visit Amphicar friends along the
way too. Any other takers out there care to join
in on an Amphicar caravan to Celina? I believe that not only should every
Amphicar owner visit Celina at least once, but every
Amphi should attend too. An adventure of a lifetime, or am I just dreaming?

Ken Chambers, CA
'64 Amphi

 

[Bill Connelly]

[...snip!] Last weekend I took the car on a 500 mile round trip to the High
Sierras for some camping and boating at a 6500 foot elevation lake just west
of Lake Tahoe. The engine ran very rich at that altitude as evidenced by
hard starting, low power output and a sooty tail pipe. Nevertheless, Amphi
performed absolutely flawlessly for the entire adventure. It handled very
well on the road, too, after the recent toe-in adjustment. Upon returning
to near sea level, I noticed that the black soot that was present inside the
tail pipe is now gone, replaced by the normal thin grayish color again. Has
anyone had any success changing the high speed metering orifice in their
Solex carb to get a leaner fuel/air mixture? Does anyone know the correct
sizes for altitude ranges? Any advice to the group would be much
appreciated.

=-=-=-=-=-=-=

Believe it or not, the topic of "Mile High Amphicars" came up on this List
just about 2 years ago. Here's an excerpt from an item I posted on the
subject fthen rom the List Archives at
http://www.escribe.com/automotive/amphicar/search.html :

EXCERPT FROM http://www.escribe.com/automotive/amphicar/m878.html , POSTED
8/9/99:

Congratz on your mutation into a webtoed motorist! Below are some comments
and replies to your questions:

> I have a couple of questions; (1) Will this car run at altitude? how about
in the water?

If you're really "up there" where the air's thinner than [insert favorite
Kate Moss anatomical metaphor here], then you may want to advance your
Amphicar's engine timing approximately one degree per thousand feet of
elevation to compensate (unlike the old Amphi, most newer vehicles perform
such ignition advance automatically by means of various sensors).

Being about a mile high up there in Aurora, Colorado, you might want to try
setting the timing about 5&1/2 to 6 degrees advanced from the 15 degrees
BTDC (i.e. Before Top Dead Center) that is given in the Amphicar Service
Manual, which is the recommended setting at sea-level, and then just see if
it runs happier. Instructions on setting the Amphicar's normal sea-level
timing are found in the Amphicar Service Manual in the appendix in the back,
on page "A/7" (These are available from Hugh Gordon, Tel. 714-523-3512). To
advance the timing from there, loosen and turn the distributor
counter-clockwise. Whatever you decide, I would DEFINITELY recommend a nice
fresh set of properly gapped spark plugs. Knowing they were perfect when
you popped them in, you can then pull them out from time to time and see
from their condition how your motor's handling things up there in the
clouds. If you're not sure what it is you should be seeing, then you'll
usually find little color photos of the conditions of spark plugs subjected
to a variety of engine conditions, including pre- and overly retarded
ignition in those Chiltons and other service manuals for this or that model
of car or motorcycle sold in most auto goods shops. Just grab any one off
the rack and start thumbing.

As for the water up there...well, water's water so long as it ain't
salty...though I'd imagine your glacier-fed lakes are probably a tad
chillier than I'm used to. So, if you've been riding your brakes all the
way down from Pike's Peak to the edge of some Coors commercial type of lake
with snickering deer or jackalopes or whatever the hell those big
dog-looking things are in the bushes there, then you may want to let your
wheels stop smoking before plowing into that icewater. I mean, we're
already fighting the laws of physics in those wheelbearings and whatnots,
but other than that, just keep it good and lubed with AMSOIL.